Robotic manipulator

Abstract

A controlled relative motion system comprising a base support, a pivot holder and a plurality of pivoting links with the pivoting links rotatably coupled to both the base support and to members of the pivot holder to rotate about axes which extend in different directions for each of these rotatable couplings in a link, typically in accord with specific geometrical arrangements, and in different directions from similar axes in another of such links. The foregoing various rotatable couplings are provided by insertable bearings or bushings in the supports and links. The pivoting links have larger portions thereof outside of the interior of the manipulator parts of which can extend outside in different directions. Such systems can incorporate a variety of force imparting members to control movements of various ones of the pivoting links or pivot holder members.

Description

CROSS-REFERENCE TO RELATED APPLICATION[0001]This application claims the benefit of U.S. Patent Application No. 60 / 664,086, filed on Mar. 22, 2005.BACKGROUND OF THE INVENTION[0002]A strong desire for increased automation in the workplace, and a desire to increase the use of animated figures depicting animals, humans or other characters in entertainment and other situations, along with an increased ability to control such mechanical manipulators has led to substantial efforts in the development of robotics. As a result, significant advances have occurred in many aspects of robotics.[0003]Perhaps the most widely used controlled component in robotic systems is a mechanical manipulator, that portion of a robot often used in connection with an end effect or to change the position or orientation of selected objects engaged by that manipulator. In many instances, such mechanical manipulators are desired to have capabilities similar to those of the human wrist or shoulder, that is, exhibitin...

AI Technical Summary

Problems solved by technology

Although a number of such mechanical manipulators have been developed which to a greater or lesser degree achieve some of these desires therefor, most have been relatively complicated devices requiring complicated components and difficult assembly procedures or both.

Many, in addition, represent compromises in having relatively limited range, or singularities within the ranges, or other limitations in performance.

However, there is much less vertical support provided to loads on the manipulable support positioned at relatively extreme angles with respect to vertical in some radial positions.

In operation, the operation of any one actuator can not be controlled independently from the others because of the unavoidable coupling between the three pivoting links.

Yet, the reduced support provided to loads on a manipulable support in the manipulator, at least when positioned at relatively extreme angles with respect to vertical in some radial positions, remains a problem.

This problem arises because the pivoting links, the rotary joints, the actuators, and even the transducers used in measuring certain variables in the manipulator during use for the manipulator control system, are compliant, or flexible, under applied loads.

This yielding makes precision positioning of the manipulable support more difficult.

The problem is further compounded by nonlinear effects such as joint backlash.

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